Jar



Jan. 12, 1943. w M. HAMON 2,307,927

-JAR Filed Nov. s, 1940 '2 shawls-sheet 1 1NvENTo1L- I B Y/ISZzeNHamon.

. Y I v ril/rnd Patented Jan. 12, 1943 UNITED STATES PATENT OFFICE JAR Weslie M. Hamon, East Los Angeles, Calif.

Application November 6, 1940, Serial No. 364,513

(Cl. Z55-27) 4 Claims.

It is afurther object of the invention to nor-`- mally lock the jar against actuation, and in the `event of the lower portion of the tool string becoming stuck in the Well, to release the jar for actuation by turning the upper portion of the tool string relative to its stuck lower portion, and to them longitudinally tension the tool string and maintain this tension while actuating the jar, with the jar actuated by rotating the upper portion of the tool string in the direction opposite to that initially employed for releasing the jar ready for actuation.

It is a still further object of the invention to provide a simple and reliable assembly, normally maintaining the tool string telescopically contracted and adapted for normal rotation of the entire string (e. g. right-hand rotation) for operating a drill or other tool which is suspended from the tool string or for connecting the tool string to an element which has been lost in the well; and in the event of the lower portion of the tool string becoming stuck in thewell, to cause relative expansion and longitudinal abutment of cooperating elements of the jar by reversely turning and then elevating the upper portion of the tool string relative to its stuck lower portion, thereby tensioning the entire tool string, with a hammer element of the jar then adapted for reciprocation relative to an anvil element of the longitudinally tensioned tool string, by again rotating the upper portion of the tool string in the iirst mentioned direction.

Further. objects of the invention will be readily understood from the following description of the accompanying drawings, in which:

Fig. 1 is an axial section through the upper portion of the jar, suspended from the upper portion of a tool string and in normal inoperative position.

Fig. 2 is an axial section through the lower portion of the jar, with the lower portion of the tool string suspended therefrom and with the jar in normal inoperative position.

Figs. 3 and 4 are transverse sections on the lines 3-3 and 4-4 respectively of Fig. 1.

Fig. 5 is a transverse section on the line 5--5 of Fig. 2.

Figs. 6 and 7 are views similar to Figs. 1 and 2 respectively, showing the jar released from normal inoperative position, ready for actuation.

Figs. 8 and 9 are views similar to Figs. 1 and 2 respectively, showing actuation of the jar.

The jar is incorporated in a tool string which is adapted for reception in a well bore, and comprises an upper mandrel I which may be suspended by a sub 2 from the upper portion 3 of the tool string which extends to the earths surface, and a lower mandrel 4 from which (by means of a sub 5) the lower portion 6 of the tool string is suspended. This lower portion of the tool string is provided at its lower end withA an element (not shown) which may be a drilling tool or the like, or which may be a spear, socket or other tool adapted to engagey an element which has been lost in the well.

The mandrels I-4 are normally telescopically contracted and locked against relative rotation and longitudinal expansion during normal rotation of the tool string, and are adapted for release of the locking means for relative rotation and for limited relative expansion of the mandrels in the event of the lower portion of the tool string becoming stuck in the well.

As an instance of means permitting limited relative expansion of the mandrels, a sleeve 1 is fixed to and projects upwardly from the mandrel 4 for telescopic reception of the lower end of the mandrel I, and an abutment 8 is provided at the upper end of this sleeve and cooperates with an abutment 9 at the lower end of the mandrel I. Anti-friction bearings I0 are preferably provided between the cooperating abutments 8-9, and are supported on the abutment 9 in longitudinally spaced relation below the abutment 8 when the mandrels are in normal telescopically contracted position (Fig. 2) but are adapted to engage the abutment 8 for limiting relative longitudinal expansion of the mandrels (Fig. 7), with thel bearings providing lantifrictional engagement.

The means for releasably locking the mandrels I-4 against relative expansion and rotation, is shown as comprising abutment, e. g. dogs I1 and I9, on the mandrel I and cooperating abutment means e. g. bayonet slots I8 and 20, fixed against rotation relative to the mandrel 4. With the parts in normal position (Fig. 1) these cooperating means longitudinally and circumferentially abut when the upper portion of the tool string (and the mandrel I) are rotated in one direction, thereby similarly rotating the mandrel 4 (and the lower portion of the tool string), and also fixing the upper and the lower portions of the tool string against relative longitudinal eX- `pansion. When the upper portion of the tool string (and the mandrel I) are turned in the opposite direction relative to the mandrel 4 (and the lower portion of the tool string), the cooperating abutments are disengaged so that elevation of the upper portion of the tool string (Fig. 6) relatively longitudinally expands the mandrels to the limit of movement permitted by the longitudinal abutment at S-Q-IU (Fig. '7), with the upper portion of the tool string (and the mandrel I) then free for rotation relative to the mandrel 4 (and the lower portion of the tool string).

As an instance, a bowl II surrounds the sleeve 1 and the mandrel I in radially spaced relation from the mandrel. At its lower end the bowl is connected to a hammer I2 which is adapted for reciprocation on the mandrel 4 with its'up- Ward movement limited by its 'engagement with an anvil I3 at the upper end of the mandrel; and the reciprocating hammer is fixed against rotation relative to the mandrel 4, as forfexample by splines i4. -A collar I is connected to the upper end of the bowl I I and a collar I5 is xed ,in the bore of the bowl below the collar I5 and above Athe 4sleeve 7, with these collars surroundvingthe mandrel I.

rIhe collars I-I and the bowl Il arelongitudinally slidable relative to the mandrel I and the mandrel is rotatable relative to the -collars and the bowl.

A dog Il on the mandrel I cooperated with a bayonet slot I8 in the collar I6, and preferably `a second dog I9 lon the mandrel I cooperates with a bayonet `slot in the collar I5. The bayonet slots Iii-Z comprise longitudinal slots I8a-2a extending downwardly from the upper -ends of the collars IIS-I5 respectively, and terminating in arcuate slots lh-20h.

`When the mandrel I is in its normal position `telescopically contracted relative to the bowl Il and the mandrel 4 (Figs. l and 2) the dogs Il--IS ,are received in the arcuate slots ISb-Zb, there- .the lower portion of the tool string) by the splined engagement I4.

If the lower portion of the tool string becomes stuck in the well so that it (and the mandrel 4) are held against elevation or rotation, the hammer I2 (and the bowl II) are also Xed against rotation by the splined engagement I 4 and areheld against elevation by the hammer E2 engaging the anvil I3. When the upper portion of the tool string (and the mandrel I) are then turned relative to the bowl Ii, in the opposite direction to that indicated by arrow A and as shown at arrow B, the dogs II-IS aline with the vlongitudinal slots Idd-20a, whereby the upper `portion of the tool string (and the mandrel I) may be elevated relative to the bowl II (and the mandrel 4 and the stuck lower portion of the tool string), to the limit or movement permitted by the abutment at t-Q-I (Figs. 6 and 7).

As a result of this longitudinal abutment at 8-9-IEL elevation of the upper portion of the tool string longitudinally tensions `the entire string; Aand this ltension vis maintained while jarring the tool string. In order to jar the tensioned tool string, the bowl i i is depressed relative to the mandrels I-4, and is then spring-elevated relative to the mandrels so that the hammer I2 strikes the anvil I3 a jarring blow. rihis alternate depression and elevation of the hammer is accomplished by rotating the upper portion of the tool spring (and the mandrel l) relative to the bowl I I (and the mandrel 4 and the lower portion of the tool string).

As an instance, a circumferential cam surface 22 is provided at the upper end of the collar I6, and the lower end of the dog Il is a cooperating cam surface IIa. With the parts in the position shown at Figs. 6 and '7, rotation of the upper portion of the tool string (and the mandrel I) relative to the bowl II circumferentially shifts the dog I7 clear of the slot Ia and engages its cam surface Ila with the cooperating cam surface 22, and then moves the cam surface I'Ia around the cooperating cam surface 22 for depressing the bowl II relative to the mandrels I-4. When nearly a complete rotation of the mandrel I has been made and just before the dog I1 again alines with the slot i3d, the parts are in the position shown at Figs. 8 and 9, with the hammer I2 depressed relative to the anvil I3; and as rotation of the mandrel I is then continued so that the dog Il again alines with the slot I8a, the bowl II andthe hammer I2 are elevated, as permitted by reception of the -dog Il in the slot I8a, thereby striking the hammer against the anvil I 3 and returning the parts to the position shown at Figs.r 6 and '7, ready for repeating the jarring action by again rotating the upper portion of the tool string.

Spring tension is preferably employed for thus elevating the depressed bowl and hammer for striking the jarring blow. As an instance, a spring 25 may surround the mandrel -I between the collar I5 and a cooperating collar 26 on the mandrel, and/or a spring 21 may surround the mandrel 4 between the hammer I2 and the sub 5. Anti-friction bearings 28 are preferably provided between the spring 25 and the collar 2t.

In operation, the dogs I'l--IS by their reception in the arcuate slots 58h-2Gb normally lock the parts in the position shown at Figs. 1 and 2, thereby providing a tool string which is rigid throughout its length and which is adapted for rotation as a unit when turned in that direction which causes abutmentof the dogs against the ends of the arcuate slots and which is the normal direction of rotation of the tool string. The threaded connections between the various parts of the jar and between the lengths of the tool string are ,preferably such as to tighten these threaded connections when the tool string is rotated in this normal direction. For example, in the illustrated embodiment wherein the normal direction of rotation is right-hand rotation as indicated by arrow A, these various threaded connections have right-hand threads.

When the lower portion of the tool string becomes stuck in the well bore so that it (and the bowl I I) cannot be elevated or rotated, the upper portion of the tool string is turned in the opposite direction relative to the now non-rotatable bowl as indicated by arrow B. The dogs II-I 9 being thus alined with the slots 28a-20a, the upper portion of the tool string (and the mandrel I) are elevated relative to the bowl I I which is now held against elevation, thereby positioning' the parts as shown at Figs. 6 and '7, with the abutmentat -89I2 maintaining any desired tension on the entire tool string. This elevationof the mandrel I partially tensions the spring 25 and elevates the dogs I1-I 9 so that the dog I9 is clear of the collar I and the dog I1 is in position ready to engage the cam surface 22.

With the desired tension then maintained on the tool string, the upper portion of the string (and the mandrel I) are rotated for engaging the dog I1 with the cam surface 22.

The cam surfaces I1a-22 are preferably arranged so that this rotation is in that direction which will tighten the threaded connections throughout the length of the tool string. For example, in the illustrated embodiment, the rotation for actuating the jar is in the direction indicated by the arrow A. During this rotation of the mandrel I, the cam engagement at I1a-22 depressed the bowl II and the hammer I2 relative to the mandrels I-4, thereby increasing the tension of the spring 25 and also tensioning the spring 21, and spacing the hammer I2 below the anvil I3 (Figs. 8 and 9); and as rotation of the mandrel I is continued the dog I1 realines with the slot I8a, whereupon the tensioned springs 25-21 elevate the bowl Il and the hammer I2 so that the latter strikes the anvil I3 a sudden jarring blow, thereby jarring the tensioned tool string and returning the parts to the. position shown at Figs. 6 and 7, ready for repeating the jarring by again rotating the upper portion of the tool string in the direction of the arrow A..

When the stuck lower portion of the tool string has been jarred loose, the tool string may be returned from its position shown at Figs. 6 and 7 to its normal position shown at Figs. l and 2, by lowering the upper portion of the tool string (and the mandrel I) for telescoping the mandrel in the sleeve 'I and lowering the dogs I1--I9 through the slots Isa-20a, and then rotating the upper portion of the tool string in the direction of arrow A for circumferentially abutting the dogs against the ends of the arcuate slots I8b--20b.

The mandrels I-4 preferably have bores I a- 4a communicating with one another and with the usual bore of the well string 3 6, for circulating a usual washing fluid during the jarring operation.

By employing the dog I9, in addition t0 the dog I1, adequate abutment surface is assured for locking the tool string in normal position for normal rotation; and by employing both the spring 25 and the spring 21, the hammer I2 may be properly tensioned for striking an adequate jarring blow against the anvil I3. By employing the anti-friction bearings I0-28 the mandrel I may be readily rotated relative to the non-ro-` tatable bowl I I and the non-rotatable sleeve 1, while the longitudinal abutment at 8-9-10 maintains any desired tension on the tool string throughout the jarring action.

I claim: Y

1. In a jar, relatively rotatable and longitudinally telescopic elements, abutments limiting relative longitudinal expansion of said elements, an anvil on one of said elements, a hammer reciprocable relative to said elements and xed against rotation relative to said one of said elements and adapted to engage the anvil for limiting reciprocation of the hammer in one direction relative to said one of said elements, a locking connection between the hammer and the other of said elements and operative when the telescopic elements are relatively contracted for xing the hammer against reciprocation in the opposite direction relative to said other of said ele-` ments, said locking means being relcasable responsive to turning said other of said elements relative to said hammer, for relative longitudinal expansion of said telescopic elements, a cam on the hammer, and a cooperating cam on said other of said elements, said cooperating cam beingoperatively positioned responsive to relative longitudinal expansion of said telescopic elements, for engaging the cam on the hammer and reciprocating the hammer relative to said one of said elements by rotating said other of said elements, for striking the anvil a jarring blow.

2. In a jar, relatively rotatable and longitudinally telescopic elements, abutments limiting relative longitudinal expansion of said elements, an anvil on one of said elements, a hammer reciprocab-le relative to said elements and fixed against rotation relative to said one of said elements and adapted to engage the anvil for limiting reciprocation of the hammer in one direction relative to said one of said elements, a spring tensioned by reciprocation of the hammer in the opposite direction relative to said one of said elements, alocking connection between the hammer and the other of said elements and operative when the telescopic elements are relatively contracted for fixing the hammer against reciprocation in the opposite direction relative to said other of said elements, said locking means being releasable responsive to turning said other of said elements relative to said hammer, for relative longitudinal expansion of said telescopic elements, a cam on the hammer, and a cooperating cam on said other of said elements, said cooperating cam being operatively positioned responsive to relative longitudinal expansion of said telescopic elements, for engaging the cam on the hammer and shifting the hammer in direction for tensioning the spring by rotating said other of said elements and for then releasing the hammer for reverse shifting by the tensioned spring for striking the anvil a jarring blow.

3. In a jar, relatively rotatable and longitudinally telescopic upper and lower mandrels, abutments limiting relative longitudinal expansion of the mandrels, an anvil on the lower mandrel, a bowl surrounding the mandrels and having a hammer suspended therefrom below the anvil and fixed against rotation but adapted for reciprocation relative to the lower mandrel, a collar xed in the bowl and surrounding the upper mandrel, a dog on the upper mandrel, a. bayonet slot in the collar adapted forreception of the dog for locking the upper mandrel against rotation in one direction relative to the bowl, and

for locking the upper mandrel against longitudinal displacement relative to the, bowl, with the mandrels relatively longitudinally contracted and the hammer abutting the anvil, said bayonet slot adapting the dog for movement therein for turning the upper mandrel in the opposite direction relative to the bowl and for relatively longitudinally expanding the mandrels for engagement of said abutments and for positioning the dog so that its lower end transversely alines with the upper end of the collar, and cooperating cam surfaces on the lower end of the clog and on the upper end of the collar, for reciprocating the bowl and the hammer relative to the mandrels by rotating the upper mandrel relative to the bowl so as to engage the cooperating cam surfaces, for striking the hammer against the anvil.

4. In a jar, relatively rotatable and longitudinally telescopic upper and lower mandrels, abutments limiting relative longitudinal expansion of the mandrels, an anvil on the lower mandrel, a bowl surrounding the mandrels` and having a hammer suspended therefrom below the anvil and iixed against rotation but adapted for reciprooation relative to the lower mandrel, a collar fixed in the bowl and surrounding the upper mandrel, a dog on the upper mandrel, a bayonet slot in the collar adapted for receptionY of the dog for locking the upper mandrel against rotation in one direction relative to the bowl, and for looking the upper mandrel against longitudinal displacement relative to the bowl, with the mandrels relatively longitudinally contracted and the hammer abutting the anvil, said bayonet slot Yadapting the dog for movement therein for turningthe `upper mandrel in the opposite direction relative tothe bowl andfor relatively longitudi nally expanding the mandrels for engagement of said abutments and for positioning the dog so that its lower end transversely alines with the upper end of the collar, a spring, and cooperating cam surfaces on the lower end of the dog and on the upper end of the collar, for depressing the bowl and the hammer relative to the mandrels by rotating the upper mandrel relative to the bowl so as to engage the cooperating cam surfaces, for tensioning the spring by said depression of the'hammer and for then` releasing the bowl and the hammer for elevation by the tensioned spring for striking the hammer against the anvil.

WESLIE M. HAMON. 

